Tool and method for removing generators



April 8, 1930. w. s. FISHER 1,753,780

r001: AND METHOD REMOVING GENERATORS I Fil'ed March :50, 1927 H E li- Hul- INVENTOR. 14444 new 5. fiSb'iZ CLAIM/$8M ATTORNEY? Patented Apr. 8,1930 WALTER S. FISHER, OF TOLEDO, OHIO,

PATENT OFFICE Y ASSIGNOB TO THE WIIiLYS-OVERLAND COMPANY, OF TOLEDO,OHIO, A COREORATION OF OHIO TOOL AND IVIETHOD FOR REItIOVINGr GENERATORSApplication filed March 30, 1927. Serial No. 179,450.

My invention relates to machines embodying sprocket and chain drivenelements which bear a definite spaced relation to each other, and it isparticularly related to a device or 5 tool by which certain of thedriven elements may be replaced without disturbing the position of theothers.

The principal object of the invention is to provide a constructionembodying sprocket 1e and chain driven members whereina shaft may beremoved without first disengaging thechain, and as an additional object,the invention contemplates the provision of an inexpensive tool by whichthe removal may be 15 performed, readily.

. Another object of the invention is to provide a construction whichwill enable one to remove a shaft without necessitating a free access tothe complete sprocket and chain to drive.

An additional object of the invention resides in the provision of anovel method of disengaging a shaft free of its chain and sprocket drivewithout dismounting the chain end while maintaining the position of thesprocket.

It is a'further object of the invention to simplify and facilitate theoperations involved in thereplacement of rotatable shafts to which thereis keyed a sprocket having a chain trained. thereover. These, togetherwith other objects,-will become more apparent from a consideration ofthe drawings and detailed description hereinafter set forth.

generator which is actuated through a chain drive from the crankshaft ofthe engine, it has been necessary to remove the chain by dismounting oneof the chain links, and subse quently, to remove the sprocket before thegenerator could be freed. Generally, the chain drive is partiallyimmersed in oil and even if actual immersion is not practiced, theelements are coated with grease. Furthermore, access to these elementsis had only. with considerable dificulty. According to my invention 1have provided a tool which is screwed into the sprocket or otherwiserigidly secured thereto, and which is capable of supporting the sprocketand chain trained thereover. The tool includes a bolt which undergoesrelative axial movement and which engages the shaft to which thesprocket is keyed. By rotating the bolt the shaft is forced out ofengagement with the sprocket leaving the sprocket and chain supported bythe tool.

A better understanding of an embodiment of my invention, which may bepreferred, can be had by referring to the accompanying drawings inwhich: 7 V

Figure I is an elevational view partly in section, of a generator andits mounting, and illustrates the relation which 'the tool elements bearto the generator elements; and

Fig. II is an end view of the tool illustrated in Fig. I.

As illustrated, a generatorhousing 1 is suitably mounted onan enginecasing 2 by means of a flexible band 8 that is adjustably secured to thecasing. Within the housing, a generator armature is rotatably mountedupon a shaft 4: that projects a short distance beyond its bearings whichare contained within the housing. Threads 6 are formed on the extremeend of the shaft which is machined to a smaller diameter than theadjacent portion to which a sprocket 7 provided with a keyway 8, isrigidly secured by a key 9 and is driven by a chain 11 that is trainedthereover. The sprocket 7 is formed with a female threaded portion 12that meshes with a male threaded portion 13 of a nut 14 hav- Accordingto the present day practice, when it is desired to remove an automobile.

ing both internal and external threads and is provided with a hexagonalhead. The internal threads of the nut accommodate a bolt 15 which may becaused to move axially into engagement with the end of the shaft byrotating the same. A cover member 16 having an aperture 17 therein forreceiving the hexagonal nut is secured to the frame or engine casing bybolts 18 and functions as a support for the nut when the shaft which,normally, is keyed'to the sprocket, is forced out of engagementtherewith.

lVhen the generator is operated a washer and nut (not shown) are fittedon the threaded end 6 of the shaft 4 to assure the proper positioning ofthe sprocket 7 with respect to the chain 11, and also to avoiddisplacement by reason of any thrust action. In order to remove thegenerator and its shaft 4:, the nut and washer (not shown) are removedand the hexagonal tool nut 14 is screwed in the sprocket 7 to assume theposition illustrated in Fig. I. Subsequently the bolt 15 is caused toengage the end of the shaft 4: and by continned rotation forces theshaft out of engagement with the sprocket. Since the octagonal nut issupported within the aperture 17 of the cover member 16, the chain andsprocket which under these conditions are secured rigidly thereto,remain in substantially their normal operative position. When it isdesired to replace the shaft 4-, the bolt is withdrawn, the shaft isreplaced and the tool nut removed. A face plate may be provided to closethe aperture in the cover member 16, thereby obviating any likelihood ofan accumulation of dirt upon the lubricated driven elements.

From the description it is obvious that although the embodimentillustrated is that of an automobile generator, the principlesunderlying the invention may be extended to other chain and sprocketdriven elements where it would be desirable to remove the shaft fromtime to time without unharnessing the sprocket as a preliminaryoperation. In like manner, the principles may be extended to a pulleyand belt drive or any other combination of power transmitting elementsin which it is desirable to maintain the position of the sprocket orpulley while the shaft supporting the same is withdrawn.

The drawings illustrated a sprocket provided with an internal threadedportion. It is to be understood, of course, that the tool may be securedto the sprocket in any desired manner, provided the combination issufliciently secure to sustain the tension of the chain or otherflexible power transmitting member. In the claims the term sprocket isemployed in a broad sense to designate a gear, pulley or the like.Similarly, the term chain is to be understood as embracing a belt, chainor any other analogous power transmitting means.

Although there is illustrated and described ut a single specificembodiment of the priniples of my invention, it will be apparent ,0those skilled the art that the invention is susceptible to manymodifications without departing from the spirit thereof, and I desiretherefore that it be limited only as indicated in the appended claims.

I claim:

1. In a machine having a rotatable shaft, a sprocket mounted thereon,and a chain trained about the sprocket; a tool for removing the shaftcomprising means adapted to engage and maintain the operative positionof the sprocket, and means operatively associated with theeagaging'means for forcing the shaft out of engagement with thesprocket.

2. In a machine having a rotatable shaft, a sprocket mounted thereon,and a chain trained about the sprocket; a tool for removing the shaftcomprising means adapted to be screwed into engagement with the sprocketand to maintain the operative position of the same, and means relativelymovable with respect to the engaging means adapted to force the shaftout of engagement with the sprocket.

3. In a machine having a rotatable shaft, a sprocket mounted thereon,and a chain trained about the sprocket; a tool for removing the shaftcomprising means adapted to engage and maintain the position of thesprocket, and a screw member mounted within the engaging and supportingmeans relatively movable therewith, adapted to force the shaft out ofengagement with the sprocket.

4. In a machine having a rotatable shaft, a sprocket having a threadedportion mounted on the shaft. and a chain trained about the sprocket; atool for removing the shaft comprising a member having a threadedportion adapted to mesh with the threaded portion of the sprocket, abolt mounted within the member adapted to be rotated into engagementwith the shaft and to force the same out of contact with the sprocket,and means for supporting and maintaining the position of the threadedmember.

5. In an automobile generator unit including a frame portion, a rotablearmature shaft mounted within the frame portion, a threaded sprocketkeyed to the shaft and a chain trained thereover; a tool for removingthe shaft while maintaining the position of the sprocket and chain,comprising a threaded member adapted to engage and mesh with thethreaded portion of the sprocket, said threaded member being providedwith a bolt adapted to be screwed axially of the shaft and intoengagement therewith and to force said shaft out of engagement with saidsprocket.

6. In an automobile generator unit including a frame portion, arotatable shaft mounted within the frame portion, an internally threadedsprocket keyed to the shaft, and a chain trained thereover; a tool forremoving the generator while maintaining the position of the sprocket orchain, comprising a nut having internal and external threads adapted tobe supported by the frame, the outer threaded surface of said nut beingadapted to mesh with the internally threaded sprocket and a bolt adaptedto mesh with the internal threads of the nut and to engage and force theshaft out of contact with the sprocket.

7. A method of repairing a device including a sprocl'ret and chaindriven shaft that comprises forcing the shaft out of engagement with thesprocket and thereafter maintaining the position of the sprocket whilereplacing the shaft.

8. The method of removing a gear driven armature and shaft supportingthe same from an automobile generator that comprises securing the geardriving the armature in its operative position independently of thearmature shaft, and forcing the shaft out of engagement with the gearwithout disturbing its relation with respect to the gear drivingelements substantially as set forth.

9. In a machine having a rotatable shaft and means for driving the shaftincluding a gear secured thereto, means for removing the shaft whilemaintaining the position of the driving means including threaded meansfor engaging and making secure the normal position of the gearindependently of the shaft, and a screw member mounted on the threadedmeans engageable with the shaft and axially movable therewith adapted toforce the shaft out of its keyed relation with respect to the ear. g Intestimony whereof, I affix my signature.

WALTER S. FISHER.

